Is Polydextrose Keto?

As the ketogenic diet grows in popularity, the food industry has responded with a wave of keto-friendly products designed to support low-carb, high-fat lifestyles.

To meet these demands, many manufacturers rely on synthetic low-carb additives such as polydextrose as bulking agents. However, this ingredient isn’t truly aligned with a health-focused keto plan.

Discover why polydextrose isn’t as keto-friendly as it seems and learn which other hidden ingredients in low-carb products are worth avoiding.

What is polydextrose?

Polydextrose is a synthetic carbohydrate, not a naturally occurring compound, and its inclusion in ketogenic products should raise concerns.

This artificial carbohydrate is produced in food manufacturing facilities by chemically synthesizing glucose, sorbitol, and citric acid, typically sourced from genetically modified (GMO) corn. This is a red flag when it comes to its use in keto-friendly products.

Its primary applications include replacing sugar, fat, and starch, improving texture, stabilizing formulations, retaining moisture, and facilitating melting and flavor release. 

Polydextrose is often favored in keto-labeled products due to its low digestible carbohydrate content, which helps minimize the net carbs of a food. 

However, its synthetic origin and highly processed nature are inconsistent with the principles of a nutrient-dense, whole-food-based ketogenic approach such as Healthy Keto®.

Polydextrose can be found in a wide range of food products, such as:

• Sugar-free and low-carb baked goods
• Protein bars and meal replacement shakes
• Reduced-calorie ice creams and frozen dairy desserts
• Low-sugar candies and chocolates
• Fiber-enriched beverages
• Breakfast cereals and granola
• Salad dressings and sauces
• Flavored yogurts and puddings
• Infant formulas

Due to its chemical composition, polydextrose cannot be digested in the small intestine, which allows it to function similarly to dietary fiber.

“While fiber is widely recognized for its role in supporting colon function and digestive health, it’s important to distinguish between naturally occurring fiber from whole foods and synthetic fibers like polydextrose,” explains Dr. Berg. 

Unlike plant-based fiber, polydextrose is artificially manufactured and lacks the full spectrum of health benefits associated with natural fiber sources.

Unfortunately, guidelines released by the Food and Drug Administration (FDA) permit polydextrose to be listed as dietary fiber on nutrition labels, which can be misleading.¹

To avoid these marketing tactics, it’s essential to read ingredient lists carefully and be aware of hidden synthetic additives that may not align with a health-conscious diet.

Watch the video below to discover nine common keto ingredients to avoid. 

Why polydextrose isn’t safe on keto

Polydextrose is often promoted as a keto-friendly ingredient due to its low calorie content and minimal impact on blood sugar and insulin levels. However, this doesn’t make it a safe or health-supportive choice for a ketogenic diet.

As a synthetic carbohydrate derived from GMO corn, polydextrose raises valid concerns. The long-term health effects of GMO consumption remain poorly understood, particularly in relation to gastrointestinal function, fertility, and liver health.

Research published in Environmental Science Europe highlights, “Serious adverse events of GM consumption include mortality, tumour or cancer, significantly low fertility, decreased learning and reaction abilities, and some organ abnormalities.”²

Furthermore, polydextrose intake can trigger digestive symptoms including abdominal cramping, bloating, excessive gas, and diarrhea. 

9 “keto” food ingredients to avoid

To truly benefit from a ketogenic lifestyle, it’s important to look beyond marketing claims and understand which ingredients may hinder your progress.

Many packaged products labeled keto-friendly contain additives and hidden carbs that can disrupt ketosis, affect your metabolism, and compromise your overall health.

Here are nine food additives to avoid on keto. 

1. Corn fiber

Corn fiber, often labeled as soluble corn fiber, is commonly used in processed foods as a sugar replacement. 

It’s typically derived from GMO corn and may trigger a range of gastrointestinal side effects. The most frequently reported issues of corn fiber include bloating, gas, abdominal cramping, and diarrhea, particularly when consumed in larger amounts.

2. Maltodextrin

Maltodextrin is a highly processed carbohydrate that can cause rapid spikes in blood sugar and insulin levels, often more dramatically than table sugar. 

Its high glycemic index makes it particularly problematic for those following a ketogenic diet, as it can quickly disrupt ketosis and interfere with fat-burning. 

3. Dextrin

Dextrin is a low-calorie bulking agent commonly used to replace sugar in processed foods, but it’s not a keto-friendly option. 

Although it’s low in calories, dextrin is high in net carbohydrates. Just one teaspoon contains approximately 3.6 grams of net carbs, making it unsuitable for those following a ketogenic diet. 

4. Dextrose

Dextrose is a synthetic sugar with a high glycemic index, meaning even small amounts can cause significant spikes in blood glucose levels, which can quickly push you out of ketosis.

Dextrose is frequently used in packaged foods as a filler in products such as candies, baked goods, sauces, and snacks, where it helps enhance sweetness and texture without adding significant cost.

5. Polydextrose

This synthetic carbohydrate is generally produced from GMO corn and isn’t a safe keto choice. 

Polydextrose is commonly used in processed foods and beverages to replace fat and sugar. Always check labels to identify products containing this additive.

6. Maltitol

Maltitol, a sugar alcohol, has a glycemic index nearly as high as that of regular sugar. It can cause significant spikes in blood sugar and insulin levels, making it unsuitable for a ketogenic diet.

7. Soy protein isolate 

Soy protein isolate is typically derived from GMO soybeans and isn’t an ideal choice for a Healthy Keto diet. 

Unlike fermented soy products such as tofu or tempeh, soy protein isolate isn’t fermented, which can make it harder on your liver and digestive system.

8. Splenda and other artificial sweeteners  

Artificial sweeteners like Splenda, also known as sucralose, as well as aspartame and saccharin, are commonly found in sugar-free foods and diet sodas. 

While they replace sugar, these sweeteners may lead to water retention, can increase the risk of insulin resistance, and have been found to disrupt the gut microbiome.

9. Tapioca starch 

Contrary to popular belief, tapioca starch isn’t suitable for keto. This common food additive is high in net carbs and lacks fat or protein, offering little nutritional value. 

Consuming even small amounts can raise your calorie intake and quickly kick you out of ketosis.

FAQ

Sources

1. https://www.fda.gov/media/113663/download ?
2. https://enveurope.springeropen.com/articles/10.1186/s12302-021-00578-9 ?